Switchable Polymers at Surfaces

Switchable Polymers at Surfaces

Switching polymers by applying an external electrical stimulus

Dipl.-Chem. Sander Klemme (2010 – 2015)

Surfaces are the interface between material and environment. If it is possible to change the surface behaviour of materials we could change the reaction of materials to environmental treatment. In this work polyelectrolyte brushes will be synthesized and the swelling behaviour of this brushes will be characterized in an external electric field. The work will be based on free radical surface polymerisation of methacrylic acid copolymers. To study the switching we use surface plasmon resonance spectroscopy and ellipsometry.

Light-responsive polymer films on solid surfaces

Dr. Helge Schenderlein (2010 – 2013)

For the development of new smart surfaces, which can be switched with respect to their properties (e.g. adhesion, wetting, or absorption) in a dynamic and reversible manner, different spiropyran-based light-switchable copolymers were synthesized and were attached covalently to solid surfaces. Upon irradiation with UV/VIS-light, these polymers undergo a reversible change within the light-sensitive group from a spiropyran (hydrophilic) to a merocyanine (hydrophobic) form in aqueous solution.For the analyzation of the polymers and the respective polymer films, as well as the switching-process different methods like ellipsometry, surface plasmon resonance spectroscopy (SPR), UV/VIS-spectroscopy, contact angle measurements are used.

Example for the switching of the conformation of surface-anchored polymer molecules by illumination with light.
Example for the switching of the conformation of surface-anchored polymer molecules by illumination with light.
Color change of a polymer solution by illumination with light of different wavelengths.
Color change of a polymer solution by illumination with light of different wavelengths.